Dental post-extractor.



T. W. ROSS. DENTAL PQsT BXTRAGTOR. APPLICATION FILED 1320.11, 1911.

Patented Aug. 13, 1912.

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4ioniriin sierras PATENT orricn.

THOMAS W. ROSS, O'F ST. LOUIS, MISSOURI.

DENTAL POST-EXTRACTOR.

To (di whom 'it may concern:

Be it known that I, 'liioiiiis lV. Ross, a citizen ot the United States of America, and a resident ot the city of St. Louis and State oit' Missouri, have invented certain new and 'useful lniprmfements in Dental Post-Extractors, of which the following is a full, clear, and exact description, reference being had to the accompanying drawing, forining part ol. this specification.

My invention relates to an improvei'nent in dental post extractors, and has for its object to provide a simple, compact and etticient. means for removing from the root ot a tooth from which the crown has broken ott' the anchor post lelt therein, so that a new post may be inserted for the new crown to be mounted on the root ot the tooth.

Another object ol my invention is lo provide a device'o'l' this character so that cach of its several parts is made detachable and replaceable, so that it' one of the parts should break it may be replaced at a Yfraction of the cost of the complete device, as well as to provide for the intercluingeable use oil gripping jaws having differently shaped gripping beaks.

Figure I is an enlarged side elevation of my invention, with part oit the supporting sleeve broken away to show a section of the interior, mounted upon a tooth with an anchor post gripped between the beaks of the jaws; said tooth and post being shown in dotted outline. Fig. II is an enlarged longitudinal section of my invention. Fig. III is an enlarged detail view, partly in section taken von line III-IIL Fig. II. Fig. IV is an enlarged detail View, partly in section, taken on line IV-IV, Fig. Il. Fig. V is an enlarged perspective view of one of the gripping jaws and retracting sprine'.

. In the accompanying drawings :.-1 designates a supporting sleeve having at one ot' its ends a collar 2 threaded thereon, said collar being preferably provided with a milled gripping surface. The sleeve is provided with a longitudinal slot, as seen at 3,

extending from substantially midway its length to the end opposite that upon which the collar 2 is mounted.

4 is a screw threaded post extending through a central perforationv in the collar 2 and inwardly into the body of the sleeve. 5 is a nut provided with an enlarged milled portion 6, threaded upon said post above said-collar, and of a diameter greater thanI Specification of Letters Patent.

Application filed December 11, 1911.

Patented Au". 13, 1912.

serial No. 665,039.

the diameter of the central perforation in the collar Q through which the post i1- passes. The post Lt terminates at its end within the supporting sleeve l in an enlarged screw threaded portion 7, having a` milled shoulder 8.

9 is a spreader depending from and preferably integrally secured to the lower end of the enlarged portion 7.

10 designates an interiorly screw threaded collar adapted to be threaded upon the enlarged screw threaded portion 7 of thc post fl, with its upper end abutting against the shoulder 8. This collar is provided with an inturned flange 10 at its lower end.

1l and ldesignate independent gripping jaws, each being provided near their upper or inner ends with shoulders 13 and l-l. 'lapered and serrated gripping beaks 11 and 12 are provided at the lower or outer end of each of said jaws.

l5 and 1G are outwardly turned flanges at vthe upper or inner ends of the jaws 11 and 12, providing transverse grooves 17 and 18 between said flanges and the shoulders 13 and let, in which grooves thc flange 10 of the collar 1() is adapted to seat. The upper or inner ends of the gri )ping jaws are provided or. their adjoining laces with longitudinal, downwardly tapering, slots, one of which is shown at 19, Fig. V. lVlien the inner 'faces ol' these jaws are placed together, these slots are adapted to register Ilarged portion 7 ot the post. Ll.

The gripping jaws 11 and 12 are detachably secured to the post 4, and abutting against 'the end of the enlarged portion 7, by being inserted into the perforation through the flanged end of the collar 10, it being understood that said collar is at this time detached from the enlarged screw threaded portion of the post ill. lVlien the inner faces of these jaws are placed together, the diameter of the combined 'shoulders 13 `and lll is greater than the diameter of the opening' 10 of the collar 10 to prevent the insertion of these gripping jaws into the opening in the llanged end of said collar beyond the upper surface ol said shoulders. 'lhe collar l0, willi the upper or inner endso'tl the gripping jaws inserted in its llanged end 10 is'then threaded upon the enlarged portion 7 of the post 4- until the spreader 9 depending from this enlarged portion 7 is forced to enter, by this threading operation, the tapered aperture formed by the registration of the longitudinal slots 19 in the flanged ends of the gripping jaws 11 and 12,` whereby said flanged ends are spread apart until the inturned flange 10 on the end of the collar 10 enters the grooves 17 and 18 above the shoulders 13 and 14- and beneath the flanges 15 and 16 on said gripping jaws, so that the bottomfaces of said fianges rest upon the inner or upper face 10 of the collar 10. The jaws 11 and 12, by the mounting which .l have described, are loosely interlocked-with the post 4 so that, `unless otherwise restrained, they would s wing together at their lower or beak portions. To hold them in a retracted position,

strap 22 are adapted for longitudinal mcvey ment, accompanying the gripping jaws, in the slot 3 of the sleeve 1.

`When it is desired to use my extractor,`

the proper adjustment upon the tooth root and anchor post is secured. The lever 21 is then moved upwardly to cause the cam to force the gripping jaws toward each other and the beaks into positive engagement with the anchor post. By reason of the pressure exerted and the frictional engagement with the edge of one of the gripping jaws, the cam holds said jaws in positive locked position. The nut 5 is then rotated, by grip--Y ping the milled portion'G, to withdraw the post 4 from the sleeve 1, which it does by reason of the fact that the inner end of the nut 5 bears-against the outer surface of the collar 2. As the post* and gripping jaws are moved upwardly through the operation refer-red to, the anchor post 24 in the root of the tooth 25(see Fig. l),is withdrawn'within the beaks l1 and 12. Vhen the anchor post is withdrawn from the root of the tooth, the cam lever 21 is moved downwardly, releasing the gripping jaws from the pressure exerted by the cam, when the spring 2O causes the bcalis 11 and 12 to retract from each other, thus freeing the anchor posts from their grip. To again permit my eX- tractor to be used, the nut 5 is rotated in a' reverse direction to that previously described, which permits the post 4 and jaws 11 and 12 tomove downwardly to any desired extent.

By the construction of the gripping jaws which I have provided, the operator is erabled to quickly substitute other gripping jaws, terminating in diiierent shaped beaks,

pointed, as may replace gripping jaws,

operating the post and jaws longitudinally of said sleeve. y

'2. A device of the character described, comprising a supporting member, a post carried by said supporting member, a pair of' gripping jaws adapted to be interlocked with and carried by said post','a spreader between the upper or-inner ends of' said jaws to interlock them tesaid` post, and means for advancing the lower or outer ends of said jaws into gripping engagement with a crown pin, and means for operating the post and jaws longitudinally .of said supporting member.. 1

` BIA device of the character described,v comprisinga sleeve, a post operable in said sleeve,'a pair of gripping jaws having longitudinally disposed slots in the upper or inner ends thereof, a spreader adapted to enter-,said slots in the upper -or inner ends of said jaws to interlock said jaws to said post, means t'or advancing the 'lower or outer ends ,of said jaws into gripping engagement with a crown pin, and means for operating the post and jaws longitudinally of said sleeve,

4. A, device of the character described, comprising a sleeve, a post operable in said sleeve, a pair of independent gripping jaws detachably carried by and interlocked to said post, a spreader between the upper or inner Vends of said jaws to interlock said jaws to said post, a cam for advancing the lower or outer ends of said jaws into gripping engagement with a crown pin, and means for operating the post and jaws longitudinally of said sleeve.

5. A. device of the character described, comprising a sleeve, a post operable in said sleeve, a pair of independent gripping jaws detachably carried by and interlocked to said post, said jaws having longitudinally disposed slots in the upper or inner ends thereof, a spreader adapted to enter said slots to interlock said jaws to said post, a cam for advancing the lower or outer ends of said jawsr into gripping engagement with a crown pin; and means for operating the post and jawsV longitudinally of said sleeve.

6. A' device of thev character described, comprising a supporting sleeve, a post longiu tudinally operable in said sleeve, a collar surrounding the end of said post within said sleeve, a pair of independent gripping jaws detachably secured tosaid post by said collar, means for expanding'the upper or inner l vja'ws longitudinally of said sleeve.

7. A device of the character described,

comprising a su orting sleeve, a post longitudinally opera le in said sleeve, a collar surrounding the end. of said post within said sleeve, said collar being flanged at its lower end, a pair of independent gripping jaws vprovided with flanges at the upper or lnner ends thereof adapted to seat upon the flange of said collar, a spreader attached to sald post and adapted to separate 4the upper or lnner ends of said gripping aws to cause the anges thereof to seatupon the flan e of said collar and to vhold the'langes o said jaws in engagement with the ange of said collar, and means for advancing the lower or4 outer ends ofsaid jaws toward each other, and means for moving said jaws and post longitudinally of said sleeve.

8.` A device of the character described,

comprising a supporting sleeve a screw threaded 0st longitudinally operhble wlthin said seeve, a nut threaded upon said post exteriorof said sleeve for operatmg said post longitudinally of said sleeve, a 3 0 collar surroun ing the end of said post within said sleeve and havin an inturned flange at its free end, a pair o independent longitudinally slotted gripping jaws provided with out-turned flanges at the upper or inner ends thereof adapted to seat upon the inturned flan e of said collar, a spreader' secured to said post and adapted to entert the slots in said ipping jaws to expand the inner ends o? flanges of said jaws in engagement withl the flange of said collar, a retracting spring between said jaws, and acam mounted upon said jaws for advancing the lower or outer ends of said jaws toward each other.

E. B. LINN, A. J. MCCAULY.

said jaws to hold the 40 

